There are conventionally known positioning methods using receiving electric field intensities of radio waves, such as Wi-Fi (registered trademark) and BLUETOOTH® Low Energy (BLE). By such positioning methods, it is difficult to accurately measure positions in some radio wave propagation environments.
Therefore, ultrawideband (UWB) communication, and positioning methods using light or sound waves have been suggested, to realize more accurate positioning on the order of several centimeters. For example, Patent Document 1 discloses a positioning system that uses light emission from a light emitter.